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Animal hormones

Amino acid derivative

① Thyroid hormones: a group of iodine containing amino acid derivatives secreted by the thyroid gland, can promote metabolism and growth and development, especially on the development and function of the central nervous system has an important impact, improve the excitability of the nervous system. Excessive secretion of thyroid hormone, resulting in hyperthyroidism; Too little secretion, adults lead to myxedema, infancy will suffer from paralysis; Iodine deficiency in the diet will cause thyroid hyperplasia, called endemic goiter, commonly known as big neck disease, China’s promotion of salt iodized comprehensive prevention measures to prevent iodine deficiency disease has a good effect, in addition, often eat kelp and other iodine-rich seaweed to prevent the disease effect is also good.

② Adrenalin: secreted by the adrenal medulla, it can promote the decomposition of liver glycogen into glucose, thereby increasing the blood sugar concentration.

③ Norepinephrine: secreted by adrenal medulla, makes arteriole shrink, blood pressure increase, and has the effect of increasing blood sugar.

Polypeptide

① Thyrotropin releasing hormone: a 3-peptide secreted by the hypothalamus, which can promote the synthesis and secretion of thyrotropin by the pituitary gland.

② Growth hormone release inhibitory hormone (somatostatin) : is a macromolecular peptide cleavage of 116 amino acids, its molecular structure is circular, there is a disulfide bond between the third and 14th cysteine, secreted by the hypothalamus, can inhibit the inappropriate secretion of growth hormone, used in the treatment of acromegaly. Early extraction from sheep brains, 500,000 sheep brains can be extracted 5μg, now using transgenic technology to obtain engineering bacteria fermentation production, 7.5 L culture medium can get 5μg.

③ gonadotropin-releasing hormone: 10 peptides secreted by the hypothalamus can promote the synthesis and secretion of gonadotropin by the pituitary gland.

④ Antidiuretic hormone: secreted by hypothalamic nerve cells and released by the posterior pituitary, it can promote the reabsorption of water by renal tubules and collecting tubules and reduce urine discharge.

⑤ Thymosin: often extracted from the thymus of calves and other medical treatments, it can promote the differentiation and maturity of T lymphocytes, enhance the function of lymphocytes, and is often used clinically to treat patients with immune dysfunction or low function (such as AIDS, systemic lupus erythematosus).

⑥ Oxytocin: secreted by hypothalamic nerve cells and released by the posterior pituitary, it can promote uterine contraction at the end of pregnancy.

7 Growth hormone releasing hormone: secreted by the hypothalamus, can promote pituitary synthesis and secretion of growth hormone.

Secretin: The first hormone to be discovered. It is an alkaline polypeptide. It consists of 27 amino acid residues and contains 11 different amino acids. Bayliss and Starling equaled the discovery in 1902. The secretin producing cells are “S” cells, mainly in the duodenal mucosa, a small amount of distribution in jejunum, ileum and antrum. Recently purified in the brain, it is also added to the list of brain-gut peptides. The function is to stimulate the pancreas to secrete a large amount of pancreatic fluid rich in bicarbonate, and the maximum stimulating dose of pancreatin for humans, dogs and pigs is 1 clinical unit per kilogram of body weight per hour by intravenous injection or intravenous infusion, equivalent to 200-250 nanograms. It has a weak strengthening effect on the secretion of pancreatic enzyme, but if given together with pancreaticozyme, it can significantly increase the secretion of pancreaticozyme, and inhibit the secretion of gastric acid and gastrointestinal activities in humans, dogs and rats. Exogenous human secretin, whose half-life is 4.1 minutes, has a metabolic clearance of 15 ml/min · kg body weight.

Proteínas

Growth hormone: synthesized and secreted by the pituitary gland, promote growth, mainly promote protein synthesis and bone growth. Excessive secretion in adults leads to acromegaly; Too much in adolescence leads to gigantism, and too little leads to dwarfism. In 1982, American scientists injected human growth hormone genes and bovine growth hormone genes into the fertilized eggs of mice, and obtained huge super mice.

② Thyroid stimulating hormone: synthesized and secreted by the pituitary gland, promote the growth and development of the thyroid gland, regulate the synthesis and secretion of thyroid hormone.

③ Gonadotropin: synthesized and secreted by the pituitary gland, promote the growth and development of the gonads, regulate the synthesis and secretion of sex hormones.

④ Prolactin: synthesized and secreted by the pituitary gland to promote mammary gland development and lactation.

⑤ Insulin: secreted by islet B cells in the pancreas, regulates sugar metabolism, reduces blood sugar content, promotes the synthesis of glycogen in blood sugar, inhibits the conversion of non-sugar substances into glucose, thus reducing blood sugar concentration. If B cells are damaged, high blood sugar occurs, leading to glycosuria.

Glucagon: secreted by islet A cells in the pancreas, it promotes glycogen decomposition and the conversion of non-sugar substances into glucose, thereby increasing blood sugar concentration.

Sterols

① Male hormone: the adrenal cortex secretes a small amount, mainly secreted by the testis, promotes the development of male reproductive organs and the formation of germ cells, stimulates and maintains male secondary sexual characteristics.

② Estrogen: the adrenal cortex secretes a small amount, mainly secreted by the ovary, promotes the development of the female reproductive organs and the formation of germ cells, stimulates and maintains the female secondary sexual characteristics and normal sexual cycle.

③ Progesterone: secreted by the ovary, promote the growth and development of endometrium and mammary gland, etc., and prepare conditions for fertilized eggs and lactation.

④ Aldosterone: secreted by the adrenal cortex, promoting the reabsorption of sodium ion (Na+) and potassium ion (K+) by the renal tubules and collecting tubules.

⑤ Glucocorticoids: secreted by the adrenal cortex, increase blood sugar, anti-allergy, anti-inflammation, anti-toxicity.

⑥ Adrenal cortex hormone: secreted by the adrenal cortex, with the control of sugar and inorganic salt metabolism, enhance the body’s defense ability.

Pheromone

There are a variety of chemical substances that can transmit information between the same insects and various insects, called signal compounds, because such chemical substances play the role of transmitting chemical information between individuals, it is called pheromones or “pheromones”. According to its different scope of action, it can also be divided into several kinds, such as sex pheromone, trace pheromone, aggregation pheromone and alarm pheromone, and the most widely used is sex pheromone.

Plant hormones

Auxin

In 1934, it was identified as indole acetic acid by Guo Ge in the United States.

① Synthetic parts: young buds, leaves and developing seeds.

② Distribution location: It is widely distributed in roots, stems, leaves, flowers, fruits, seeds and coleoptile, and mostly concentrated in the parts of vigorous growth, such as coleoptile, bud and root apex meristem, cambium, developing seeds and fruits.

③ Main role: auxin content in the plant body is very small, 7 million corn seedlings stem tips, only contains 1 mg of plant auxin, but auxin has a huge effect on the growth of plants. Promote rooting of cuttings, cultivate rootless bean sprouts, promote fruit development, cultivate seedless fruits, prevent falling flowers and fruit, bonsai modeling cultivation, hedge pruning and fruit tree pruning; Plant tissue culture can affect dedifferentiation and redifferentiation of plant cells.

Cytokinin

It is a kind of plant hormone with adenine ring structure.

① Synthesis site: exists in the part of the cell division, mainly the root tip.

② Main role: promote cell division and tissue differentiation, plant tissue culture can affect plant cell dedifferentiation and redifferentiation.

Gibberellin

It is a class of plant hormones belonging to diterpenoids.

Synthetic site: It is generally synthesized in young buds, young roots and immature seeds.

② Main role: through leaves, shoots, flowers, seeds or fruits into the plant body, conduction to the growth of active parts of the effect, promote cell elongation, thereby causing stem elongation and plant increase; It can break the dormancy of organs such as seeds, tubers or bulbs and promote seed germination and fruit ripening.

Abscisic acid

It is a plant hormone with sesquiterpene structure.

① Synthetic parts: root crown, wilted leaf tissue, mature fruit, seeds and stems.

② Location of distribution: It is abundant in the organs and tissues that will be shed.

③ Main function: inhibit cell division (deoxyribonucleic acid and protein synthesis), promote leaf and fruit aging and shedding.

Ethylene:

It’s a gas hormone.

① Synthetic site: It is widely present in a variety of tissues of plants, especially in mature fruits.

② Main function: promote fruit ripening.

Plant pigments

The pigments in plant cells mainly exist in chloroplasts, chromatids, vacuoles and other organelles.

Chlorophyll

It exists in chloroplasts and contains more than carotenoids. It mainly absorbs red orange light and blue violet light, including chlorophyll a and clorofila b, among which chlorophyll b is yellow-green and transmits the absorbed light energy to a few special states of chlorophyll a; Chlorophyll a is blue-green, and a few special states of chlorophyll a can accept most of the light energy transmitted by chlorophyll A, all of the chlorophyll b, lutein and carotene, and then be excited to release high-energy electrons to complete the photoelectric conversion.

Carotenoides

Carotenoid content is less than chlorophyll, mainly absorbs blue-violet light, and can transfer the absorbed light energy to a few special states of chlorophyll; Carotenoids include lutein and carotene, where lutein is yellow and carotene is orange-yellow.

Antocianinas

It exists in the cell fluid of roots, leaves, flowers, pericarp, seed coat, etc. Its color varies depending on the pH, being red under acidic conditions and blue under alkaline conditions.

Phycoerythrin

A red, spectral pigment found in cyanobacteria and red algae that absorbs blue-green light, so red algae can live in the deep sea. Phycobilins also include phycocyanin, phycoxanthin and phycothrin. Different photosynthetic pigments absorb different wavelengths of light. Phycobilin mainly absorbs some green light, orange-red light and other long wave light. In addition to chlorophyll, kelp cells contain phyxanthin, which is why kelp is brown. In addition to chlorophyll, porphyra cells also contain phycocyanin and phycocyanin, so it is purple.

Animal pigments

Melanin

Dark brown pigment in the skin or hair of animals, especially vertebrates. It is synthesized by melanocytes and widely exists in human skin, mucous membrane, retina, pia, gall bladder and ovary. Albino patients have a genetic abnormality that prevents them from converting tyrosinase into melanin. They exhibit white hair, reddish skin, and photophobia. When the melanocytes at the base of human hair age, the activity of tyrosinase in the cells decreases, resulting in gray hair.

Lipofuscin

It will gradually accumulate in the skin cells as the cells age and form age spots.

Vitamins

Vitamin A

Also known as anti-dry eye vitamins, contained in animal foods such as liver and cod liver oil, plant foods do not contain, but carotene in plants such as carrots can be converted into vitamin A, which can promote human growth and development and enhance resistance. Lack of prone to night blindness, skin keratinization and other diseases.

Vitamina B1

Also known as thiamine, mainly contained in rice and wheat and other grain seed coats, can maintain the normal metabolism of the human body and the normal physiological function of the nervous system, the lack of human body will cause beriberi, neuritis and other diseases.

Vitamina C

Also known as antiseptic acid, mostly contained in fresh fruits and vegetables, with strong reductibility, can reduce I2 to I-, in the solution containing vitamin C, adding starch solution can be used to titrate the vitamin C in the tested sample, lack of scurvy and other diseases.

Vitamin D

It belongs to sterols, which are more abundant in cod liver oil, egg yolk, liver and other foods, and can promote the absorption of Ca and P in the small intestine. Lack of it can lead to diseases such as rickets and osteoporosis.

Vitamin E

Because it is related to fertility, it is also known as tocopherol, which belongs to phenolic compounds. Vitamin E is related to the biological function of animals. When animals lack vitamin E, their reproductive organs are damaged and infertile. Vitamin E is very easy to oxidize, can protect other substances from oxidation, is the most effective antioxidant in animals and humans, can fight against the lipid peroxidation of biofilm, protect the integrity of biofilm structure and function, and delay aging.

Vitamina K

Coagulation effect; It helps to repair and grow bone cells.

Biotina

Vitamin H, which is abundant in liver, kidney, yeast and milk, is a growth factor for glutamate.